reserve a,b,c,d,m,x,n,j,k,l for Nat,
  t,u,v,z for Integer,
  f,F for FinSequence of NAT;
reserve p,q,r,s for real number;

theorem
  n>0 & not t divides (t+z)|^n implies not t divides z
  proof
    assume n>0 & not t divides (t+z)|^n;
    then not t divides t+z by Th14;
    hence thesis by WSIERP_1:4;
  end;
